The plan to use hydrogen as fuel to run a small fleet of vehicles, to ferry athletes from their “village” to the contest arenas during the forthcoming Commonwealth Games in Delhi, is experimental in nature, but a “first” nonetheless in a city which has put its entire public transport system on the pollution-free compressed natural gas (CNG). The world is looking to hydrogen as a future source of clean energy to run automobiles and also to power factories, businesses and homes. Hydrogen is of course the most abundantly available element on earth. When used as fuel in an engine, it is reckoned to be about 30 per cent more efficient than conventional fuels like petrol. And when it is used through the fuel cell route, its efficiency betters petrol by between 100 per cent and 200 per cent. The Indian Oil Corporation, which has mooted the plan to operate hydrogen vehicles during the Commonwealth Games, plans to use a mix of hydrogen and CNG in a 20:80 ratio. Such a mix will require only minor adjustments in engines that are already using CNG. Several leading international vehicle companies have already put hydrogen vehicles on the road in the US, Canada, Europe and elsewhere. Some Indian automobile manufacturers have developed prototypes of vehicles that can be driven using hydrogen, and are likely to test-drive them soon.
These examples notwithstanding, there are quite a few technical issues which need to be tackled before hydrogen can become a practical and economically viable vehicular fuel. Despite being plentiful, hydrogen is invariably found in compound form, such as in combination with oxygen in water, or in combination with carbon in hydrocarbons like methane and coal. A major challenge before scientists and engineers is how to produce it at a cost lower than competing conventional fuels. Besides, as a gas, hydrogen is voluminous, requiring large tanks to store it for the uninterrupted running of vehicles over long distances. Its most efficient and practical use, therefore, is deemed to be in the form of hydrogen-based fuel cells but that technology is still evolving. At present, these cells are costly to produce. Intensive research and development work is on in several countries to refine this technology, so hydrogen could well become cost-effective before long.
India is has made a belated beginning in this field and is now trying to play catch-up. While the initial attempts have been oriented towards using hydrogen as engine fuel, singly or in combination with CNG, work is simultaneously apace to develop fuel cell technology. The Indian Space Research Organisation (Isro) is collaborating with vehicle manufacturers to develop hydrogen fuel cells for automobiles, using the cryogenic technology which it evolved for advanced rocket launch vehicles. Hydrogen and atmospheric oxygen will combine in these cells to produce electricity to drive vehicles in a pollution-free manner, emitting nothing more than water vapour as exhaust. Considering the potential that hydrogen holds out as a renewable and sustainable source of clean energy, and its positive implications for energy security, the work should get appropriate funding and priority.
